Results 41 to 50 of about 256 (175)
The Astrophysical Journal, 2023 We present the first results from the Southern Hemisphere Parallax Interferometric Radio Astrometry Legacy Survey: 10 μ as accurate parallaxes and proper motions for two Southern Hemisphere 6.7 GHz methanol masers obtained using the inverse MultiView ...
L. J. Hyland +13 more
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Advances in Astronomy, Volume 2026, Issue 1, 2026.The continued detection of near‐Earth asteroids with postulated close encounters with Earth is a clear motivation for planetary defense–driven mission designs. Fast reconnaissance in an imminent threat scenario (i.e., less than a few years upon impact) is crucial to gain information about an asteroid potentially impacting the Earth in the near future ...
Markus Patzek +11 more
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The Astrophysical Journal LettersPublished analyses of very long baseline interferometry data for the sources included in the third International Celestial Reference Frame catalog have revealed object-specific, excess astrometric variability and quasi-coherent trajectories as functions ...
Valeri V. Makarov +5 more
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Single-band VLBI Absolute Astrometry
The Astronomical Journal, 2023 The ionospheric path delay impacts single-band, very long baseline interferometry (VLBI) group delays, which limits their applicability for absolute astrometry.
Leonid Petrov
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Advances in Astronomy, Volume 2026, Issue 1, 2026.This paper investigates the degradation of pointing accuracy in the Kunming 40‐m radio telescope due to long‐term equipment aging and environmental disturbances. Conventional linear pointing models are constrained by their linear modeling framework, making it difficult to accurately represent the nonlinear errors induced by temperature, wind speed, and
Yao He +3 more
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The Radio Parallax of the Crab Pulsar: A First VLBI Measurement Calibrated with Giant Pulses
The Astrophysical Journal, 2023 We use four observations with the European very long baseline interferometry (VLBI) network to measure the first precise radio parallax of the Crab Pulsar. We found two in-beam extragalactic sources just outside the Crab Nebula, with one bright enough to
Rebecca Lin +4 more
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Satellites and Small Bodies With ALMA: Insights Into Solar System Formation and Evolution
AGU Advances, Volume 6, Issue 6, December 2025.Abstract Our understanding of the formation and evolution of planetary systems has made major advances in the past decade. This progress has been driven in large part by the Atacama Large Millimeter/submillimeter Array (ALMA), which has given us an unprecedented view of solar system bodies themselves, and of the structure and chemistry of forming ...
Katherine de Kleer +3 more
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The Present Status of Astrometry at Optical and Radio Wavelengths [PDF]
Symposium - International Astronomical Union, 1994 A Review is presented of the present status of astrometry towards defining a radio/optical reference frame.
openaire +1 more source
A Radio Counterpart to a Jupiter-mass Binary Object in Orion
The Astrophysical Journal LettersUsing James Webb Space Telescope near-infrared data of the inner Orion Nebula, Pearson & McCaughrean detected 40 Jupiter-mass binary objects (JuMBOs).
Luis F. Rodríguez +2 more
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Reassessing the Relationship Between Meteor Radio Afterglows and Optical Persistent Trains
Journal of Geophysical Research: Space Physics, Volume 130, Issue 9, September 2025.Abstract Meteor radio afterglows (MRAs) and optical persistent trains (PTs) are two types of long‐lived phenomena which are occasionally observed following the occurrence of a meteor. Both phenomena are thought to be produced by intrinsic emission mechanisms; PTs have been associated with chemiluminescent reactions between meteoric metals and ...
L. E. Cordonnier +5 more
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